[petsc-dev] asm / gasm
Fande Kong
fdkong.jd at gmail.com
Fri Jun 24 23:38:23 CDT 2016
Hi Barry,
Is this a right way to create the branch corresponding to the commit:
e12b4729b15ad5de2ed17324d40445da9b32e630.
(1) git clone https://Fande-Kong@bitbucket.org/petsc/petsc.git petsc-dev
(2) cd petsc-dev
(3) git checkout master
(4) git branch Fande-Kong/gasm_bugs_scatter
e12b4729b15ad5de2ed17324d40445da9b32e630
(5) git checkout Fande-Kong/gasm_bugs_scatter
Where could I get the data files "~/Datafiles/matrices/poisson2 "? What
specific configuration options are you using?
Fande Kong,
On Fri, Jun 24, 2016 at 7:56 PM, Fande Kong <fdkong.jd at gmail.com> wrote:
> Hi Barry,
>
> I will be debugging into it, and will let you know as soon as possible.
>
> Fande,
>
> On Fri, Jun 24, 2016 at 7:48 PM, Barry Smith <bsmith at mcs.anl.gov> wrote:
>
>>
>> Fande,
>>
>> Based on my bisection I got the results
>>
>>
>> There are only 'skip'ped commits left to test.
>> The first bad commit could be any of:
>> 08902ef530872fd742dc4ae06e5f55514aa5a6f4
>> c14adfe1f4858fc4a331628e0999094c88508aa6
>> 25623ae837111235baaf8310854f127ee4f5d849
>> f771a2744df1b1e04cbde7267f90af2b8dd270ea
>> bac5b06fd7acf2dbdffb3ef782ccfe7a95cc790d
>> da8d96df7d39c0e17cff0758e470753f324e2e80
>> 4bb724134134efafd385bc6b729da2f75e5ded03
>> 930d09c13c6be24c34efcb20ee858969724c0dd9
>> b9d0fdaa8b8fd04b16ee28e86ef9a83a5d6857d0
>> We cannot bisect more!
>> ~/Src/petsc ((6a644ab...)|BISECTING) arch-basic
>>
>> Before these commits
>>
>> src/ksp/ksp/examples/tutorials/ex10 ran fine with
>>
>> petscmpiexec -valgrind -n 2 ./ex10 -f0 ~/Datafiles/matrices/poisson2
>> -ksp_type cg -ksp_monitor_short -ksp_rtol 1.e-8 -pc_type gamg -pc_gamg_type
>> agg -pc_gamg_agg_nsmooths 1 -pc_gamg_coarse_eq_limit 100
>> -pc_gamg_reuse_interpolation true -pc_gamg_square_graph 1
>> -pc_gamg_threshold 0.0 -ksp_converged_reason -use_mat_nearnullspace true
>> -mg_levels_ksp_max_it 2 -mg_levels_ksp_type chebyshev
>> -mg_levels_esteig_ksp_type cg -mg_levels_esteig_ksp_max_it 10
>> -mg_levels_ksp_chebyshev_esteig 0,0.05,0,1.05 -mg_levels_pc_type sor
>> -mat_block_size 1 -pc_gamg_use_agg_gasm -mg_levels_pc_type gasm -ksp_view
>>
>> after these commits it ran with a valgrind error
>>
>> $ petscmpiexec -valgrind -n 2 ./ex10 -f0 ~/Datafiles/matrices/poisson2
>> -ksp_type cg -ksp_monitor_short -ksp_rtol 1.e-8 -pc_type gamg -pc_gamg_type
>> agg -pc_gamg_agg_nsmooths 1 -pc_gamg_coarse_eq_limit 100
>> -pc_gamg_reuse_interpolation true -pc_gamg_square_graph 1
>> -pc_gamg_threshold 0.0 -ksp_converged_reason -use_mat_nearnullspace true
>> -mg_levels_ksp_max_it 2 -mg_levels_ksp_type chebyshev
>> -mg_levels_esteig_ksp_type cg -mg_levels_esteig_ksp_max_it 10
>> -mg_levels_ksp_chebyshev_esteig 0,0.05,0,1.05 -mg_levels_pc_type sor
>> -mat_block_size 1 -pc_gamg_use_agg_gasm -mg_levels_pc_type gasm -ksp_view
>>
>> ==10897== Invalid write of size 8
>> ==10897== at 0x100E79764: PCSetUp_GASM (gasm.c:432)
>> ==10897== by 0x100F35D3E: PCSetUp (precon.c:984)
>> ==10897== by 0x101024208: KSPSetUp (itfunc.c:332)
>> ==10897== by 0x100F14059: PCSetUp_MG (mg.c:773)
>> ==10897== by 0x100E9C2C1: PCSetUp_GAMG (gamg.c:734)
>> ==10897== by 0x100F35D3E: PCSetUp (precon.c:984)
>> ==10897== by 0x101024208: KSPSetUp (itfunc.c:332)
>> ==10897== by 0x100005C48: main (in ./ex10)
>> ==10897== Address 0x103d8baa8 is 0 bytes after a block of size 3,880
>> alloc'd
>> ==10897== at 0x100019EBB: malloc (in
>> /usr/local/Cellar/valgrind/3.11.0/lib/valgrind/vgpreload_memcheck-amd64-darwin.so)
>> ==10897== by 0x1000D925C: PetscMallocAlign (mal.c:34)
>> ==10897== by 0x1002BA3D2: VecCreate_MPI_Private (pbvec.c:491)
>> ==10897== by 0x1002BAEAC: VecCreate_MPI (pbvec.c:535)
>> ==10897== by 0x1002ECFBE: VecSetType (vecreg.c:53)
>> ==10897== by 0x1002BB2B0: VecCreate_Standard (pbvec.c:562)
>> ==10897== by 0x1002ECFBE: VecSetType (vecreg.c:53)
>> ==10897== by 0x1003F1A2F: MatCreateVecs (matrix.c:8653)
>> ==10897== by 0x100E78DE9: PCSetUp_GASM (gasm.c:396)
>> ==10897== by 0x100F35D3E: PCSetUp (precon.c:984)
>> ==10897== by 0x101024208: KSPSetUp (itfunc.c:332)
>> ==10897== by 0x100F14059: PCSetUp_MG (mg.c:773)
>> ==10897== by 0x100E9C2C1: PCSetUp_GAMG (gamg.c:734)
>> ==10897== by 0x100F35D3E: PCSetUp (precon.c:984)
>> ==10897== by 0x101024208: KSPSetUp (itfunc.c:332)
>> ==10897== by 0x100005C48: main (in ./ex10)
>> ==10897==
>> [1]PETSC ERROR: --------------------- Error Message
>> --------------------------------------------------------------
>> [1]PETSC ERROR: Nonconforming object sizes
>> [1]PETSC ERROR: Vector wrong size 1078034432 for scatter 950 (scatter
>> forward and vector to != ctx to size)
>> [1]PETSC ERROR: See http://www.mcs.anl.gov/petsc/documentation/faq.html
>> for trouble shooting.
>> [1]PETSC ERROR: Petsc Development GIT revision: v3.6.1-1135-ge12b472 GIT
>> Date: 2015-09-26 21:43:36 -0600
>> [1]PETSC ERROR: ./ex10 on a arch-basic named Barrys-MacBook-Pro.local by
>> barrysmith Fri Jun 24 20:44:37 2016
>> [1]PETSC ERROR: Configure options --with-fc=0 --download-sowing=0
>> --with-mpi-dir=/Users/barrysmith/libraries
>> [1]PETSC ERROR: #1 VecScatterBegin() line 1689 in
>> /Users/barrysmith/Src/petsc/src/vec/vec/utils/vscat.c
>> [1]PETSC ERROR: #2 PCSetUp_GASM() line 437 in
>> /Users/barrysmith/Src/petsc/src/ksp/pc/impls/gasm/gasm.c
>> [1]PETSC ERROR: #3 PCSetUp() line 984 in
>> /Users/barrysmith/Src/petsc/src/ksp/pc/interface/precon.c
>> [1]PETSC ERROR: #4 KSPSetUp() line 332 in
>> /Users/barrysmith/Src/petsc/src/ksp/ksp/interface/itfunc.c
>> [1]PETSC ERROR: #5 PCSetUp_MG() line 773 in
>> /Users/barrysmith/Src/petsc/src/ksp/pc/impls/mg/mg.c
>> [1]PETSC ERROR: #6 PCSetUp_GAMG() line 734 in
>> /Users/barrysmith/Src/petsc/src/ksp/pc/impls/gamg/gamg.c
>> [1]PETSC ERROR: #7 PCSetUp() line 984 in
>> /Users/barrysmith/Src/petsc/src/ksp/pc/interface/precon.c
>> [1]PETSC ERROR: #8 KSPSetUp() line 332 in
>> /Users/barrysmith/Src/petsc/src/ksp/ksp/interface/itfunc.c
>> [1]PETSC ERROR: #9 main() line 312 in
>> /Users/barrysmith/Src/petsc/src/ksp/ksp/examples/tutorials/ex10.c
>> [1]PETSC ERROR: PETSc Option Table entries:
>> [1]PETSC ERROR: -f0 /Users/barrysmith/Datafiles/matrices/poisson2
>> [1]PETSC ERROR: -ksp_converged_reason
>> [1]PETSC ERROR: -ksp_monitor_short
>> [1]PETSC ERROR: -ksp_rtol 1.e-8
>> [1]PETSC ERROR: -ksp_type cg
>> [1]PETSC ERROR: -ksp_view
>> [1]PETSC ERROR: -malloc_test
>> [1]PETSC ERROR: -mat_block_size 1
>> [1]PETSC ERROR: -mg_levels_esteig_ksp_max_it 10
>> [1]PETSC ERROR: -mg_levels_esteig_ksp_type cg
>> [1]PETSC ERROR: -mg_levels_ksp_chebyshev_esteig 0,0.05,0,1.05
>> [1]PETSC ERROR: -mg_levels_ksp_max_it 2
>> [1]PETSC ERROR: -mg_levels_ksp_type chebyshev
>> [1]PETSC ERROR: -mg_levels_pc_type gasm
>> [1]PETSC ERROR: -pc_gamg_agg_nsmooths 1
>> [1]PETSC ERROR: -pc_gamg_coarse_eq_limit 100
>> [1]PETSC ERROR: -pc_gamg_reuse_interpolation true
>> [1]PETSC ERROR: -pc_gamg_square_graph 1
>> [1]PETSC ERROR: -pc_gamg_threshold 0.0
>> [1]PETSC ERROR: -pc_gamg_type agg
>> [1]PETSC ERROR: -pc_gamg_use_agg_gasm
>> [1]PETSC ERROR: -pc_type gamg
>> [1]PETSC ERROR: -use_mat_nearnullspace true
>> [1]PETSC ERROR: ----------------End of Error Message -------send entire
>> error message to petsc-maint at mcs.anl.gov----------
>> application called MPI_Abort(MPI_COMM_WORLD, 60) - process 1
>> ~/Src/petsc/src/ksp/ksp/examples/tutorials ((e12b472...)) arch-basic
>>
>> in commit e12b4729b15ad5de2ed17324d40445da9b32e630
>>
>> so you either did not make the vector you are accessing large enough or
>> you are accessing its values incorrectly. Could you please see if you can
>> determine the bug so we can get GASM back on track. I urge you to debug in
>> the branch e12b4729b15ad5de2ed17324d40445da9b32e630 or before to find your
>> error not in master since master has so many additional changes. Once you
>> have found the bug we can work together to port the fix up to maint or
>> master
>>
>> Thanks
>>
>> Barry
>>
>>
>>
>>
>>
>> > On Jun 24, 2016, at 9:35 AM, Fande Kong <fdkong.jd at gmail.com> wrote:
>> >
>> >
>> > Message: 5
>> > Date: Fri, 24 Jun 2016 08:59:57 -0500
>> > From: Barry Smith <bsmith at mcs.anl.gov>
>> > To: Mark Adams <mfadams at lbl.gov>
>> > Cc: For users of the development version of PETSc
>> > <petsc-dev at mcs.anl.gov>
>> > Subject: Re: [petsc-dev] asm / gasm
>> > Message-ID: <55FF6E27-46B0-4729-9A52-37C5ABBCC0CF at mcs.anl.gov>
>> > Content-Type: text/plain; charset="us-ascii"
>> >
>> >
>> > > On Jun 24, 2016, at 1:35 AM, Mark Adams <mfadams at lbl.gov> wrote:
>> > >
>> > >
>> > >
>> > > On Thu, Jun 23, 2016 at 11:46 PM, Barry Smith <bsmith at mcs.anl.gov>
>> wrote:
>> > >
>> > > Mark,
>> > >
>> > > It is not as simple as this to convert to ASM. It will take a
>> little bit of work to use ASM here instead of GASM.
>> > >
>> > >
>> > > Just to be clear: ASM used to work. Did the semantics of ASM change?
>> >
>> > Hi Mark,
>> >
>> > Assume that you said GASM used to work, and now is not working any more.
>> >
>> > GASM was originally written by Dmitry. The basic idea is to allow
>> mulit-rank blocks, that is, a mulit-rank subdomain problem could be solved
>> using a small number of processor cores in parallel. This is different from
>> ASM.
>> >
>> > I was involved into the development of GASM last summer. There are some
>> changes:
>> >
>> > (1) Added a function to increase overlap of the multi-rank subdomains.
>> The function is called by GASM in default.
>> >
>> > (2) Added a hierarchical partitioning to optimize data exchange. Ensure
>> that small subdomains in a multi-rank subdomain are geometrically
>> connected. GASM does not use this functionality in default.
>> >
>> > Any way, if you have an example (like Barry asked) showing the broken
>> GASM, I will debug into it (of course, if Barry does not mind).
>> >
>> > Fande Kong,
>> >
>> >
>> > Show me a commit where ASM worked! Do you mean that the GASM
>> worked? The code has GASM calls in it, not ASM so how could ASM have
>> previously worked? It is possible that something changed in GASM that broke
>> GAMG's usage of GASM. Once you tell me how to reproduce the problem with
>> GASM I can try to track down the problem.
>> >
>> > >
>> > > But before that please please tell me the command line argument
>> and example you use where the GASM crashes so I can get that fixed. Then I
>> will look at using ASM instead after I have the current GASM code running
>> again.
>> > >
>> > > In branch mark/gamg-agg-asm in ksp ex56, 'make runex56':
>> >
>> > I don't care about this! This is where you have tried to change from
>> GASM to ASM which I told you is non-trivial. Give me the example and
>> command line where the GASM version in master (or maint) doesn't work where
>> the error message includes ** Max-trans not allowed because matrix is
>> distributed
>> >
>> > We are not communicating very well, you jumped from stating GASM
>> crashed to monkeying with ASM and now refuse to tell me how to reproduce
>> the GASM crash. We have to start by fixing the current code to work with
>> GASM (if it ever worked) and then move on to using ASM (which is just an
>> optimization of the GASM usage.)
>> >
>> >
>> > Barry
>> >
>> >
>> > >
>> > > 14:12 nid00495 ~/petsc/src/ksp/ksp/examples/tutorials$ make runex56
>> > > [0]PETSC ERROR: --------------------- Error Message
>> --------------------------------------------------------------
>> > > [0]PETSC ERROR: Petsc has generated inconsistent data
>> > > [0]PETSC ERROR: MPI_Allreduce() called in different locations (code
>> lines) on different processors
>> > > [0]PETSC ERROR: See
>> http://www.mcs.anl.gov/petsc/documentation/faq.html for trouble shooting.
>> > > [0]PETSC ERROR: Petsc Development GIT revision: v3.7.2-633-g4f88208
>> GIT Date: 2016-06-23 18:53:31 +0200
>> > > [0]PETSC ERROR:
>> /global/u2/m/madams/petsc/src/ksp/ksp/examples/tutorials/./ex56 on a
>> arch-xc30-dbg64-intel named nid00495 by madams Thu Jun 23 14:12:57 2016
>> > > [0]PETSC ERROR: Configure options --COPTFLAGS="-no-ipo -g -O0"
>> --CXXOPTFLAGS="-no-ipo -g -O0" --FOPTFLAGS="-fast -no-ipo -g -O0"
>> --download-parmetis --download-metis --with-ssl=0 --with-cc=cc
>> --with-clib-autodetect=0 --with-cxx=CC --with-cxxlib-autodetect=0
>> --with-debugging=1 --with-fc=0 --with-shared-libraries=0 --with-x=0
>> --with-mpiexec=srun LIBS=-lstdc++ --with-64-bit-indices
>> PETSC_ARCH=arch-xc30-dbg64-intel
>> > > [0]PETSC ERROR: #1 MatGetSubMatrices_MPIAIJ() li
>> > >
>> > >
>> > >
>> > >
>> > >
>> > >
>> > >
>> > >
>> > >
>> > >
>> > > Barry
>> > >
>> > >
>> > > > On Jun 23, 2016, at 4:19 PM, Mark Adams <mfadams at lbl.gov> wrote:
>> > > >
>> > > > The question boils down to, for empty processors do we:
>> > > >
>> > > > ierr = ISCreateGeneral(PETSC_COMM_SELF, 0, NULL, PETSC_COPY_VALUES,
>> &is);CHKERRQ(ierr);
>> > > > ierr = PCASMSetLocalSubdomains(subpc, 1, &is,
>> NULL);CHKERRQ(ierr);
>> > > > ierr = ISDestroy(&is);CHKERRQ(ierr);
>> > > >
>> > > > or
>> > > >
>> > > > PCASMSetLocalSubdomains(subpc, 0, NULL, NULL);
>> > > >
>> > > > The later gives and error that one domain is need and the later
>> gives an error (appended).
>> > > >
>> > > > I've checked in the code for this second error in ksp (make runex56)
>> > > >
>> > > > Thanks,
>> > > >
>> > > > [0]PETSC ERROR: --------------------- Error Message
>> --------------------------------------------------------------
>> > > > [0]PETSC ERROR: Petsc has generated inconsistent data
>> > > > [0]PETSC ERROR: MPI_Allreduce() called in different locations (code
>> lines) on different processors
>> > > > [0]PETSC ERROR: See
>> http://www.mcs.anl.gov/petsc/documentation/faq.html for trouble shooting.
>> > > > [0]PETSC ERROR: Petsc Development GIT revision:
>> v3.7.2-633-g4f88208 GIT Date: 2016-06-23 18:53:31 +0200
>> > > > [0]PETSC ERROR:
>> /global/u2/m/madams/petsc/src/ksp/ksp/examples/tutorials/./ex56 on a
>> arch-xc30-dbg64-intel named nid00495 by madams Thu Jun 23 14:12:57 2016
>> > > > [0]PETSC ERROR: Configure options --COPTFLAGS="-no-ipo -g -O0"
>> --CXXOPTFLAGS="-no-ipo -g -O0" --FOPTFLAGS="-fast -no-ipo -g -O0"
>> --download-parmetis --download-metis --with-ssl=0 --with-cc=cc
>> --with-clib-autodetect=0 --with-cxx=CC --with-cxxlib-autodetect=0
>> --with-debugging=1 --with-fc=0 --with-shared-libraries=0 --with-x=0
>> --with-mpiexec=srun LIBS=-lstdc++ --with-64-bit-indices
>> PETSC_ARCH=arch-xc30-dbg64-intel
>> > > > [0]PETSC ERROR: #1 MatGetSubMatrices_MPIAIJ() line 1147 in
>> /global/u2/m/madams/petsc/src/mat/impls/aij/mpi/mpiov.c
>> > > > [0]PETSC ERROR: #2 MatGetSubMatrices_MPIAIJ() line 1147 in
>> /global/u2/m/madams/petsc/src/mat/impls/aij/mpi/mpiov.c
>> > > > [1]PETSC ERROR: --------------------- Error Message
>> --------------------------------------------------------------
>> > > >
>> > > > On Thu, Jun 23, 2016 at 8:05 PM, Barry Smith <bsmith at mcs.anl.gov>
>> wrote:
>> > > >
>> > > > Where is the command line that generates the error?
>> > > >
>> > > >
>> > > > > On Jun 23, 2016, at 12:08 AM, Mark Adams <mfadams at lbl.gov> wrote:
>> > > > >
>> > > > > [adding Garth]
>> > > > >
>> > > > > On Thu, Jun 23, 2016 at 12:52 AM, Barry Smith <bsmith at mcs.anl.gov>
>> wrote:
>> > > > >
>> > > > > Mark,
>> > > > >
>> > > > > I think there is a misunderstanding here. With GASM an
>> individual block problem is __solved__ (via a parallel KSP) in parallel by
>> several processes, with ASM each block is "owned" by and solved on a single
>> process.
>> > > > >
>> > > > > Ah, OK, so this is for multiple processors in a block. Yes, we
>> are looking at small, smother, blocks.
>> > > > >
>> > > > >
>> > > > > With both the "block" can come from any unknowns on any
>> processes. You can have, for example a block that comes from a region
>> snaking across several processes if you like (or it makes sense due to
>> coupling in the matrix).
>> > > > >
>> > > > > By default if you use ASM it will create one non-overlapping
>> block defined by all unknowns owned by a single process and then extend it
>> by "one level" (defined by the nonzero structure of the matrix) to get
>> overlapping.
>> > > > >
>> > > > > The default in ASM is one level of overlap? That is new. (OK, I
>> have not looked at ASM in like over 10 years)
>> > > > >
>> > > > > If you use multiple blocks per process it defines the
>> non-overlapping blocks within a single process's unknowns
>> > > > >
>> > > > > I assume this still chops the matrix and does not call a
>> partitioner.
>> > > > >
>> > > > > and extends each of them to have overlap (again by the non-zero
>> structure of the matrix). The default is simple because the user only need
>> indicate the number of blocks per process, the drawback is of course that
>> it does depend on the process layout, number of processes etc and does not
>> take into account particular "coupling information" that the user may know
>> about with their problem.
>> > > > >
>> > > > > If the user wishes to defined the blocks themselves that is
>> also possible with PCASMSetSubLocalSubdomains(). Each process provides 1 or
>> more index sets for the subdomains it will solve on. Note that the index
>> sets can contain any unknowns in the entire problem so the blocks do not
>> have to "line up" with the parallel decomposition at all.
>> > > > >
>> > > > > Oh, OK, this is what I want. (I thought this worked).
>> > > > >
>> > > > > Of course determining and providing good such subdomains may not
>> always be clear.
>> > > > >
>> > > > > In smoothed aggregation there is an argument that the aggregates
>> are good, but the scale is fixed obviously. On a regular grid smoothed
>> aggregation wants 3^D sized aggregates, which is obviously wonderful for
>> AMS. And for anisotropy you want your ASM blocks to be on strongly
>> connected components, which is what smoothed aggregation wants (not that I
>> do this very well).
>> > > > >
>> > > > >
>> > > > > I see in GAMG you have PCGAMGSetUseASMAggs
>> > > > >
>> > > > > But the code calls PCGASMSetSubdomains and the command line is
>> -pc_gamg_use_agg_gasm, so this is all messed up. (more below)
>> > > > >
>> > > > > which sadly does not have an explanation in the users manual and
>> sadly does not have a matching options data base name
>> -pc_gamg_use_agg_gasm following the rule of drop the word set, all lower
>> case, and put _ between words the option should be -pc_gamg_use_asm_aggs.
>> > > > >
>> > > > > BUT, THIS IS THE WAY IT WAS! It looks like someone hijacked this
>> code and made it gasm. I never did this.
>> > > > >
>> > > > > Barry: you did this apparently in 2013.
>> > > > >
>> > > > >
>> > > > > In addition to this one you could also have one that uses the
>> aggs but use the PCASM to manage the solves instead of GASM, it would
>> likely be less buggy and more efficient.
>> > > > >
>> > > > > yes
>> > > > >
>> > > > >
>> > > > > Please tell me exactly what example you tried to run with what
>> options and I will debug it.
>> > > > >
>> > > > > We got an error message:
>> > > > >
>> > > > > ** Max-trans not allowed because matrix is distributed
>> > > > >
>> > > > > Garth: is this from your code perhaps? I don't see it in PETSc.
>> > > > >
>> > > > > Note that ALL functionality that is included in PETSc should have
>> tests that test that functionality then we will find out immediately when
>> it is broken instead of two years later when it is much harder to debug. If
>> this -pc_gamg_use_agg_gasm had had a test we won't be in this mess now.
>> (Jed's damn code reviews sure don't pick up this stuff).
>> > > > >
>> > > > > First we need to change gasm to asm.
>> > > > >
>> > > > > We could add this argument pc_gamg_use_agg_asm to ksp/ex56
>> (runex56 or make a new test). The SNES version (also ex56) is my current
>> test that I like to refer to as recommended parameters for elasticity. So
>> I'd like to keep that clean, but we can add junk to ksp/ex56.
>> > > > >
>> > > > > I've done this in a branch mark/gamg-agg-asm. I get an error
>> (appended). It looks like the second coarsest grid, which has 36 dof on one
>> processor has an index 36 in the block on every processor. Strange. I can
>> take a look at it later.
>> > > > >
>> > > > > Mark
>> > > > >
>> > > > > > [3]PETSC ERROR: [4]PETSC ERROR: --------------------- Error
>> Message --------------------------------------------------------------
>> > > > > > [4]PETSC ERROR: Petsc has generated inconsistent data
>> > > > > > [4]PETSC ERROR: ith 0 block entry 36 not owned by any process,
>> upper bound 36
>> > > > > > [4]PETSC ERROR: See
>> http://www.mcs.anl.gov/petsc/documentation/faq.html for trouble shooting.
>> > > > > > [4]PETSC ERROR: Petsc Development GIT revision:
>> v3.7.2-630-g96e0c40 GIT Date: 2016-06-22 10:03:02 -0500
>> > > > > > [4]PETSC ERROR: ./ex56 on a arch-macosx-gnu-g named
>> MarksMac-3.local by markadams Thu Jun 23 06:53:27 2016
>> > > > > > [4]PETSC ERROR: Configure options COPTFLAGS="-g -O0"
>> CXXOPTFLAGS="-g -O0" FOPTFLAGS="-g -O0" --download-hypre=1
>> --download-parmetis=1 --download-metis=1 --download-ml=1 --download-p4est=1
>> --download-exodus=1 --download-triangle=1
>> --with-hdf5-dir=/Users/markadams/Codes/hdf5 --with-x=0 --with-debugging=1
>> PETSC_ARCH=arch-macosx-gnu-g --download-chaco
>> > > > > > [4]PETSC ERROR: #1 VecScatterCreate_PtoS() line 2348 in
>> /Users/markadams/Codes/petsc/src/vec/vec/utils/vpscat.c
>> > > > > > [4]PETSC ERROR: #2 VecScatterCreate() line 1552 in
>> /Users/markadams/Codes/petsc/src/vec/vec/utils/vscat.c
>> > > > > > [4]PETSC ERROR: Petsc has generated inconsistent data
>> > > > > > [3]PETSC ERROR: ith 0 block entry 36 not owned by any process,
>> upper bound 36
>> > > > > > [3]PETSC ERROR: See
>> http://www.mcs.anl.gov/petsc/documentation/faq.html for trouble shooting.
>> > > > > > [3]PETSC ERROR: Petsc Development GIT revision:
>> v3.7.2-630-g96e0c40 GIT Date: 2016-06-22 10:03:02 -0500
>> > > > > > [3]PETSC ERROR: ./ex56 on a arch-macosx-gnu-g named
>> MarksMac-3.local by markadams Thu Jun 23 06:53:27 2016
>> > > > > > [3]PETSC ERROR: Configure options COPTFLAGS="-g -O0"
>> CXXOPTFLAGS="-g -O0" FOPTFLAGS="-g -O0" --download-hypre=1
>> --download-parmetis=1 --download-metis=1 --download-ml=1 --download-p4est=1
>> --download-exodus=1 --download-triangle=1
>> --with-hdf5-dir=/Users/markadams/Codes/hdf5 --with-x=0 --with-debugging=1
>> PETSC_ARCH=arch-macosx-gnu-g --download-chaco
>> > > > > > [3]PETSC ERROR: #1 VecScatterCreate_PtoS() line 2348 in
>> /Users/markadams/Codes/petsc/src/vec/vec/utils/vpscat.c
>> > > > > > [3]PETSC ERROR: #2 VecScatterCreate() line 1552 in
>> /Users/markadams/Codes/petsc/src/vec/vec/utils/vscat.c
>> > > > > > [3]PETSC ERROR: #3 PCSetUp_ASM() line 279 in
>> /Users/markadams/Codes/petsc/src/ksp/pc/impls/asm/asm.c
>> > > > >
>> > > > >
>> > > > >
>> > > > >
>> > > > >
>> > > > >
>> > > > >
>> > > > > Barry
>> > > > >
>> > > > >
>> > > > >
>> > > > >
>> > > > >
>> > > > >
>> > > > > > On Jun 22, 2016, at 5:20 PM, Mark Adams <mfadams at lbl.gov>
>> wrote:
>> > > > > >
>> > > > > >
>> > > > > >
>> > > > > > On Wed, Jun 22, 2016 at 8:06 PM, Barry Smith <
>> bsmith at mcs.anl.gov> wrote:
>> > > > > >
>> > > > > > I suggest focusing on asm.
>> > > > > >
>> > > > > > OK, I will switch gasm to asm, this does not work anyway.
>> > > > > >
>> > > > > > Having blocks that span multiple processes seems like over kill
>> for a smoother ?
>> > > > > >
>> > > > > > No, because it is a pain to have the math convolved with the
>> parallel decompositions strategy (ie, I can't tell an application how to
>> partition their problem). If an aggregate spans processor boundaries, which
>> is fine and needed, and let's say we have a pretty uniform problem, then if
>> the block gets split up, H is small in part of the domain and convergence
>> could suffer along processor boundaries. And having the math change as the
>> parallel decomposition changes is annoying.
>> > > > > >
>> > > > > > (Major league overkill) in fact doesn't one want multiple
>> blocks per process, ie. pretty small blocks.
>> > > > > >
>> > > > > > No, it is just doing what would be done in serial. If the cost
>> of moving the data across the processor is a problem then that is a
>> tradeoff to consider.
>> > > > > >
>> > > > > > And I think you are misunderstanding me. There are lots of
>> blocks per process (the aggregates are say 3^D in size). And many of the
>> aggregates/blocks along the processor boundary will be split between
>> processors, resulting is mall blocks and weak ASM PC on processor
>> boundaries.
>> > > > > >
>> > > > > > I can understand ASM not being general and not letting blocks
>> span processor boundaries, but I don't think the extra matrix communication
>> costs are a big deal (done just once) and the vector communication costs
>> are not bad, it probably does not include (too many) new processors to
>> communicate with.
>> > > > > >
>> > > > > >
>> > > > > > Barry
>> > > > > >
>> > > > > > > On Jun 22, 2016, at 7:51 AM, Mark Adams <mfadams at lbl.gov>
>> wrote:
>> > > > > > >
>> > > > > > > I'm trying to get block smoothers to work for gamg. We
>> (Garth) tried this and got this error:
>> > > > > > >
>> > > > > > >
>> > > > > > > - Another option is use '-pc_gamg_use_agg_gasm true' and use
>> '-mg_levels_pc_type gasm'.
>> > > > > > >
>> > > > > > >
>> > > > > > > Running in parallel, I get
>> > > > > > >
>> > > > > > > ** Max-trans not allowed because matrix is distributed
>> > > > > > > ----
>> > > > > > >
>> > > > > > > First, what is the difference between asm and gasm?
>> > > > > > >
>> > > > > > > Second, I need to fix this to get block smoothers. This used
>> to work. Did we lose the capability to have blocks that span processor
>> subdomains?
>> > > > > > >
>> > > > > > > gamg only aggregates across processor subdomains within one
>> layer, so maybe I could use one layer of overlap in some way?
>> > > > > > >
>> > > > > > > Thanks,
>> > > > > > > Mark
>> > > > > > >
>> > > > > >
>> > > > > >
>> > > > >
>> > > > >
>> > > >
>> > > >
>> > >
>> > >
>> >
>> >
>> >
>> > ------------------------------
>> >
>> > _______________________________________________
>> > petsc-dev mailing list
>> > petsc-dev at mcs.anl.gov
>> > https://lists.mcs.anl.gov/mailman/listinfo/petsc-dev
>> >
>> >
>> > End of petsc-dev Digest, Vol 90, Issue 30
>> > *****************************************
>> >
>>
>>
>
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